Answer:
[tex]t = \frac{15}{f}[/tex]
Explanation:
Light travels with the speed of light in a free space vacuum
In a piece of glass . the light travels at a speed [tex]v = \frac{c}{n}[/tex]
where ;
n = index of refraction
The time [tex]t = \frac{L}{v}[/tex]
where;
L = length of the glass slab
velocity [tex]v = \frac{d}{t}[/tex]
[tex]t= \frac{d}{v}[/tex]
[tex]t = \frac{L}{\frac{c}{n}} \\\\t = \frac {n * L}{c}[/tex]
Also; [tex]c =\lambda f[/tex]
[tex]t = \frac{n*L}{\lambda f}[/tex]
Given that;
wavelength [tex]\lambda = L/10[/tex]; and n = 1.5; we have:
[tex]t = \frac{n*L}{\frac{L}{10} f}[/tex]
[tex]t = \frac{10*n}{f}[/tex]
[tex]t = \frac{10*1.5}{f}[/tex]
[tex]t = \frac{15}{f}[/tex]
